共查询到19条相似文献,搜索用时 578 毫秒
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王玮茹 《电网与水力发电进展》2011,27(6):61-64
介绍了光伏发电过程中最大功率点跟踪(MPPT)原理,并简要分析了常规控制算法在最大功率跟踪控制中的优缺点,提出将模糊自适应PI控制算法应用到光伏系统最大功率点跟踪的控制中,该控制方法能快速响应外界环境的变化,获得系统最大功率点,且可以有效消除系统在最大功率点附近的振荡现象,提高系统的稳定性。仿真结果表明,该方法能使系统稳定地工作在最大功率点,并且控制精度高,能灵敏反应外界环境的变化。 相似文献
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一种光伏MPPT模糊控制算法研究 总被引:10,自引:0,他引:10
针对太阳能光伏阵列的工作特性,在现有最大功率跟踪控制方法的基础上,提出了一种光伏MPPT的模糊控制算法——变步长扰动观察法.从偏差和偏差变化率的角度,将寻优分为二个阶段(第一阶段应用扰动观察法并设置较大步长快速接近最大功率点附近,第二阶段采用变步长的方法向最大功率点进一步逼近并至最佳),实现了光伏系统快速和高精度的跟踪要求.系统中引入了工作状态的判断环节,可以根据环境的变化,做出相应反应,提高了系统的快速跟踪性能和稳定性. 相似文献
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针对风光联合发电系统,文章提出了一种基于Cuk变换器电路的分时进行光伏电池和永磁风机最大输出功率跟踪的新控制方法。采用模糊控制算法对光伏电池和永磁风机最大输出功率跟踪进行了变步长确定。试验测试表明:对光伏电池和永磁风机的最大输出功率跟踪进行分时控制方案可行。采用模糊规则库确定步长效果良好,并且整体系统具有良好的经济实用性。 相似文献
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在局部阴影的情况下,由于串联式光伏组件的输出特性不同而产生多个极值点,使得传统的最大功率追踪(maximum power point tracking, MPPT)方法陷入局部极值点而失效。文中提出一种针对两级并网光伏系统的改进电导增量法以适应光伏阵列在局部阴影下的多峰值最大功率跟踪,通过分析最大功率点电压的变化范围,设定最大功率电压搜索范围以提高搜索效率,并通过DC/DC Boost变换器占空比实现输入电压控制,保证算法不陷入局部极值点。最后利用仿真实验验证了该算法在有、无阴影情况下均能准确地跟踪光伏方阵最大功率,有效提高了光伏阵列输出效率。 相似文献
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基于中值步长法的光伏阵列最大功率点跟踪 总被引:1,自引:0,他引:1
提出了光伏阵列最大功率点跟踪的新型变步长扰动观察法,即中值步长法。在外界环境发生变化时,利用斜率判断扰动方向,利用启动步长快速跟踪光伏阵列最大功率点的大概位置;然后每扰动一次就将扰动步长取中值,使系统在稳态时最大限度地逼近最大功率点,减小最大功率点附近的震荡,提高跟踪精度;利用功率判断避免在扰动过程中出现算法错误。通过Matlab进行仿真,证明了中值步长法能达到理想的跟踪效果。 相似文献
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Maximum power point tracking using adaptive fuzzy logic control for grid-connected photovoltaic system 总被引:1,自引:0,他引:1
Nopporn Patcharaprakiti Suttichai Premrudeepreechacharn Yosanai Sriuthaisiriwong 《Renewable Energy》2005,30(11):1693
This paper proposes a method of maximum power point tracking using adaptive fuzzy logic control for grid-connected photovoltaic systems. The system is composed of a boost converter and a single-phase inverter connected to a utility grid. The maximum power point tracking control is based on adaptive fuzzy logic to control a switch of a boost converter. Adaptive fuzzy logic controllers provide attractive features such as fast response, good performance. In addition, adaptive fuzzy logic controllers can also change the fuzzy parameter for improving the control system. The single phase inverter uses predictive current control which provides current with sinusoidal waveform. Therefore, the system is able to deliver energy with low harmonics and high power factor. Both conventional fuzzy logic controller and adaptive fuzzy logic controller are simulated and implemented to evaluate performance. Simulation and experimental results are provided for both controllers under the same atmospheric condition. From the simulation and experimental results, the adaptive fuzzy logic controller can deliver more power than the conventional fuzzy logic controller. 相似文献
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New maximum power point tracker for PV arrays using fuzzy controller in close cooperation with fuzzy cognitive networks 总被引:1,自引:0,他引:1
The studies on the photovoltaic (PV) generation are extensively increasing, since it is considered as an essentially inexhaustible and broadly available energy resource. However, the output power induced in the photovoltaic modules depends on solar radiation and temperature of the solar cells. Therefore, to maximize the efficiency of the renewable energy system, it is necessary to track the maximum power point of the PV array. In this paper, a maximum power point tracker using fuzzy set theory is presented to improve energy conversion efficiency. A new method is proposed, by using a fuzzy cognitive network, which is in close cooperation with the presented fuzzy controller. The new method gives a very good maximum power operation of any PV array under different conditions such as changing insolation and temperature. The simulation studies show the effectiveness of the proposed algorithm. 相似文献
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《全球能源互联网(英文)》2021,4(5):441-452
The resiliency of a standalone microgrid is of considerable issue because the available regulation measures and capabilities are limited. Given this background, this paper presented a new mathematical model for a detailed photovoltaic (PV) module and the application of new control techniques for efficient energy extraction. The PV module employs a single-stage conversion method to integrate it with the utility grid. For extraction the maximum power from PV and integrate it to power grid, a three-phase voltage source converter is used. For obtaining the maximum power at a particular irradiance a maximum power point tracking (MPPT) scheme is used. The fuzzy logic control and adaptive network-based fuzzy inference system are proposed for direct current (DC) link voltage control. The proposed model and control scheme are validated through a comparison with the standard power-voltage and current–voltage charts for a PV module. Simulation results demonstrate that the system stability can be maintained with the power grid and in the island mode, in contrast with the MPPT. 相似文献
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针对含储能装置的传统光伏虚拟同步发电机(PV-VSG)不仅投资成本高且未考虑光伏阵列输出特性的问题,提出一种基于滑模变功率点跟踪(SM-VPT)的PV-VSG控制策略。该方法在滑模控制的基础上引入直流母线电压偏差控制,调整光伏阵列的功率跟踪轨迹,实现光伏出力自适应匹配负载需求,即当光伏容量充足时,只提供与负载相匹配的功率;光伏功率不足时,可实现传统的MPPT控制以减少电力短缺,同时防止直流电压骤降,保证系统稳定运行。该方法使PV-VSG能够按需向负载供电,无需增加额外的储能设备,可实现光伏发电系统直接以VSG形式接入并网,仿真结果验证了所提控制方法的有效性。 相似文献
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Dynamic voltage restorer (DVR) is used to protect sensitive loads from voltage disturbances of the distribution generation (DG) system. In this paper, a new control approach for the 200 kW solar photovoltaic grid connected system with perturb and observe maximum power point tracking (MPPT) technique is implemented. Power quality improvement with comparison is conducted during fault with proportional integral (PI) and artificial intelligence-based fuzzy logic controlled DVR. MPPT tracks the actual variable DC link voltage while deriving the maximum power from a photovoltaic array and maintains DC link voltage constant by changing modulation index of the converter. Simulation results during fault show that the fuzzy logic based DVR scheme demonstrates simultaneous exchange of active and reactive power with less total harmonic distortion (THD) present in voltage source converter (VSC) current and grid current with fast tracking of optimum operating point at unity power factor. Standards (IEEE-519/1547), stipulates that the current with THD greater than 5% cannot be injected into the grid by any distributed generation source. Simulation results and validations of MPPT technique and operation of fuzzy logic controlled DVR demonstrate the effectiveness of the proposed control schemes. 相似文献